目前，我国共有盐湖1500多个，包括青海湖，罗布泊盐湖，纳木错等著名盐湖，总面积约5万多平方公里，年产盐6000万吨。输盐泵作为输盐系统的的核心设备之一，用于盐场输送饱和卤水与盐晶的固液混合物，在盐卤开采、输运过程中有重要应用。多年来，受到设计条件及试验条件的限制，市场上尚无专门的输盐泵定型产品。因此，设计并优化专业的输盐泵产品对于采盐、输盐行业提升产盐能力、改善经济效益很有必要。本文根据输盐泵的性能要求，设计并优化了双流道泵和常规叶片式离心泵。采用UN NX 6.0对叶轮和蜗壳进行了三维建模，并用ANSYS CFX 18.2软件对输盐泵内的清水定常、非定常及固液定常流动展开了数值模拟。结果表明：双流道泵的内部流动较为复杂，在叶轮入口和叶片压力侧附近存在较强的分离涡，并且分离涡的形成与脱落和蜗壳与叶轮间的动静干涉有关。随着流量增大，分离涡逐渐减少，流态变得较为光滑顺畅。双流道泵的效率比普通离心泵低3%~8%，最优效率点往往在大流量工况下取得，本文中设计工况下水力效率为73.2%，扬程为23.7m，最有效率点在1.3Qd时取得。由于双通道泵的截面尺寸较大，固体颗粒在流道中流动较为平稳。经现场测试表明，相比普通离心泵，双流道泵运输盐时颗粒的破碎率有所降低。此外，双流道泵叶片前缘容易受到冲蚀磨损，蜗壳壁面易受到滑动磨损，随着颗粒粒径增大，磨损率增加。对双流道泵的优化结果表明，包角取200°时，外特性和内部流动特性最好，包角过大，反而不利于对流动的控制；单个流道截面变化规律取下圆弧式变化时水力效率和内部流动状况最优；双流道泵的蜗壳宜选用螺旋形蜗壳，出口方式以侧面出口为佳。对常规叶片离心泵而言，包角和叶片数是重要的设计参数，计算结果表明，随着包角和叶片数的增加，水利效率和扬程逐渐增大。离心泵在包角为150°，叶片数为5时综合性能最佳。颗粒在离心泵中的轨迹偏向于叶片压力面和后盖板方向，叶轮中磨损严重的区域是叶片前缘和尾缘。随着包角的增加，颗粒更容易在叶片出口处发生碰撞，叶片尾缘的磨损更为严重。随着叶片数的增加，颗粒向压力面和后盖板方向偏转的趋势更加明显，后盖板上的磨损情况加重。

At present, there are more than 1,500 salt lakes in China, with a total area of more than 50,000 square kilometers and a broad coastline that can provide sea salt saltworks. As one of the core equipment of salt transportation system, salt pump is used to transport mixture of saturated brine and salt crystals in salt field. It has important application in the process of salt mining and transportation. Over the years, limited by the design conditions and test conditions, there is no special salt pump products on the market. Therefore, the design and development of professional salt pump products for salt industry to enhance their salt production capacity, and improve their economic efficiency is necessary.In this paper, according to the performance requirements of salt pump, double channel pump and centrifugal pump are designed and optimized. The impeller and volute were three-dimensionally modeled using UN NX 6.0. The numerical simulation was carried out using ANSYS CFX 18.2 software, the steady, unsteady flow of clean water, steady flow of two phase situations are calculated and analyzed. The results show:1. For conventional centrifugal pumps, the wrap angle and the number of vanes are important design parameters. The calculated results show that the efficiency and head of pump increase with the increase of wrap angle and number of vanes. Centrifugal pump with wrap angle of 150 °, and blade number of 5 has the best overall performance.2. The particle trajectory in the centrifugal pump is biased toward the pressure side of the blade and the hub. The areas with serious wear condition are the leading edge and the trailing edge of the blade. As the wrap angle increases, the particles more easily collide at the exit of the blade, and the wear of the trailing edge of the blade becomes more serious. As the number of blades increases, the tendency of the particles to deflect toward the pressure surface and the hub becomes more pronounced, and the wear on the rear cover is aggravated.3. The internal flow of the double channel pump is very complicated. There is a strong separation vortex near the inlet of the impeller and the pressure side of the blade, and the formation and shedding of the separation vortex are related to the static and dynamic interference between the volute and the impeller. Besides, as the flow rate increases, the separation vortex decreases and the fluid flow becomes smoother.4. The efficiency of double channel pump is lower than that of ordinary centrifugal pump by 3% ~ 8%, and the optimal efficiency is often obtained under large flow conditions. In this paper, the hydraulic efficiency under design conditions is 73.2%, and the head is 23.7 m, efficiency point obtained at 1.3 Qd.5. Due to the larger cross-section size of the double channel pump, solid particles flow more smoothly in the flow channel. The field test shows that, compared with ordinary centrifugal pump, salt particle crushing rate obviously decreased in double channel pump.As for the erosion rate, the leading edge of the double-flow pump blade is vulnerable to erosion wear, the volute wall is vulnerable to sliding wear, with the particle size increases, the wear rate increases.6. The results of the optimization of dual-channel pump show that when the wrap angle is 200°, the hydraulic performance and the inner flow characteristic are the best. When the change regulation of the cross-section of the channel is like a throw arc, the hydraulic efficiency and the internal flow condition are the best.As for the volute, spiral volute with a side diffuser is better.